as2 - disable keydown function

is there a way to disable the left arrow key for a certain part of a movie. i have the follow code to make it work but need the code to disable it.

//listen for keypress

var myListener:Object = new Object();
myListener.onKeyDown = function() {
if (Key.getCode() == Key.LEFT) {
_global.slidecounter -= 2;
gotoAndPlay(2);
} else if (Key.getCode() == Key.RIGHT) {
slidePlayer.play();
} else if (Key.getCode() == Key.DOWN) {
gotoAndPlay(2);
} else if (Key.getCode() == Key.UP) {
_global.slidecounter -= 2;
gotoAndPlay(2);
}
};
Key.addListener(myListener);

any help would be great thanks, Dan